This invention relates to a ribbon lift device for a printer for selectively moving a print ribbon and a correction or erase ribbon to a print or correction allowing position by means of a cam mechanism.
Ribbon lift devices of the type described above are known in the art, and a typical one of such conventional device is disclosed, for example, in Japanese laid-open Pat. No. 56-161190. The conventional device includes a single controlling cam which has a common cam track and separate cam tracks corresponding to a print ribbon and a correction or erase ribbon formed therein so that rotation of the controlling cam in a forward or reverse direction may selectively displace the print ribbon or the correction ribbon to a print position for printing of a character or for correction of a character printed. However, since the conventional device is designed so as to attain different selective operations by forward or reverse rotation of the single controlling cam, an arrangement or construction of such cam tracks, a cam follower and so on becomes complicated and must be made in high accuracy, resulting in difficulty in production and assembly. Besides, it has another drawback that detection of a position of the controlling cam and controlling such as controlling of an amount of rotation of the controlling cam inevitably become complicated and difficult.